Closed-link brake hanger



Original Filed Feb. 5. 1923 INVENTOR Q Z Z Patented Oct. 25, 1927.

UNHTED S'IATES.

PATENT OFFICE.

FREDERIC SCHAEFER, OF PITTSBURGH, PENNSYLVANIA.

CLOSED-LINK BRAKE HANGER.

This application is a division of my copendlng application Serial No. 616,693, filed Februar Y 3 1923 iertainin to closed link brake hangers for use on railway cars to suspend brake beams from truck frames. In that application there is disclosed an improved closed link brake hanger and method of manufacturing it, the claims being directed towards the method of manufacture. In this application the claims are directed towards the improved brake hanger itself.

Brake hangers are subjected to a great variety and range of stresses, and must be as strong and durable as possible because failure of one of them is liable to drop a brake beam in front of a car wheel and cause derailment. The prevailing practice in the manufacture of closed link brake hanger is to bend a rod or bar to the desired shape and weld its adjacent ends to each other. Because of the necessity of welding, the steel of which the brake hangers have been manufactured, must be, and has been, low carbon, which cannot be hardened to effectively resist the wear to which the hangers are subjected.

The object of this invention is to provide a closed-link brake hanger which is strong, durable and highly resistant to wear.

The closed-link brake hanger provided accordin to this invention has two side arms and upper and lower yokes connecting the ends of the side arms. The hanger is formed of a single unwelded piece of steel which is relatively high in carbon, containing for eX ample :trom about .40 to 80% carbon. The steel blank of which the hanger is formed i forged and bent by a series of steps into the desired ultimate shape and form, and when completed it is subjected to the necessary heat treatment for hardening it, with the ultimate result that there is produced a hardened brake hanger which very effectively resists the almost continuous wear to which the upper and lower yokes of the brake hanger are subjected. It made of selfhardening steel, the brake hangers may be air hardened and drawn from a suitable temperature. Otherwise they should be quenched and drawn.

By reason of the fact that the brake hanger is formed from a single piece of unwelded steel, it does not have a plane of potential weakness, such as is characteristic of prior brake hangers, and which has been Divided and this application filed June responsible for serious accidents due to breakage of the hangers at their weld points; andby reason of the fact that the brake hanger is formed of relatively high carbon steel it is capable of taking and maintaining a hardened form which resists wear of its upper and lower yokes, and materially prolongs its life.

Theimproved brake hanger is illustrated in the accompanying drawings which also show the several successive steps in the course of its manufacture. In these drawings Fig. 1 is a plan view of a steel blank after the first forging operation has been performed upon it; Fig. 2 a transverse sect-ional view taken on the line IIII, Fig. 1; Fig. 3 a View corresponding to Fig. 2 after another operation has been performed upon the blank; Fig. 4; a plan View of the hanger after a still further step has been performed upon the blank, the blank of Figs. 1 and 3 being indicated in dotted lines; Fig. 5 a View of one form of the finished brake hanger; Fig. 6 a transverse sectional view of the lower transverse yoke of the hanger, the plane of view being indicated by the line IV'IV, Fig. 5; and Fig. 7 a plan view of another form of finished brake hanger.

In the first step of the manufacture of the brake hanger, an integral steel rod or bar of any suitable or desired cross-sectional shape is forged into the form of an elongate closed link having two sides 1 and 1 with an intermediate narrow slot 2 between them, as shown in Fig. 1. Usually there is a thin web 3 between the sides 1 and 1" after the forging operation, which web may be readily stamped out or otherwise removed so that the blank will have a completely open slot as shown in Fig. 3.

The elongate link of Fig. 1 is subjected to an expanding operation in which the sides 1 and 1 form the transverse yokes and side arms of the hanger. This may be accomplished by forcing the elongate blank of Figs. 1 and 3 over a suitably shaped expanding tool. lVhen the final brake hanger is of truly rectangular form, such as illus trated in Fig. 4, the sides of the elongate link are preferably so expanded that each side 1 and 1 forms one transverse yoke and one side arm of the hanger. In Fig. 4c the elongated link illustrated in dotted lines is so expanded that the side 1 forms the transverse upper yoke 4. and the side arm 5 of the hanger, and the side 1 forms the side arm 6 and transverse yoke 7 of the hanger.

The lower transverse yoke may be subjected to a forging operation to give it any desired shape, as for example to bring it into the shape of an asymmetric I-beam, as

illustrated in Figs. 5 and 6, this particular form of lower yoke being disclosed and intermediate of their ends.

h to effectively resist Wear. In actual practice a In the closed-link brake hanger shown in Figs. 5 and 7, a'ndin any other specific form which may be made embodying the invention, each hanger is formed of a single piece of untvelded relatively high carbon steel, and is hardened by a suitable heattreatment it has been found that brake hangers eme 'bodying this invention may, because of their wear-resisting properties, be used more than twice as long as those heretofore produced, and in no instance has a brake hanger embodying this invention failed by reason of an inherent plane of Weakness.

I claim as my invention: Q LA forged GlOSBd-rllIlk brake hanger consisting of two side arms andupper and lower yokes connecting the ends of the side ,arms, the entire brake hanger being ilormedv of a single unWelded piece or" relativelyhigh carbon steel and hardened to resist Wear.

2. A forged closed-link brake hanger consisting 01' two side arms and upper and lower yokes connecting the ends of the side arms, the entire brake hanger being formed of a single unwelded piece of steel containing from about 10 to .80% carbon and hardened to resist. Wear. A

In testimony whereof, I sign my name.

EREDERIC SCI-IAEFER. 

